Many types of apparatus for storage or transportation of tools or accessories are commercially available. The apparatus may be made of metal or plastic. Certain apparatus are provided with multiple independent accessory cases which can be ordered in any sequence. Other apparatus are provided with multiple independent accessory cases which are pivotal with respect to each other.
U.S. Pat. No. 5,259,502 discloses an assembly of multiple tool cases which are connected to each other by an axle or inserting rod so that they are pivotal with respect to the axle or inserting rod such that the tool case can be selectively opened. In this way, the assembly of tool cases forms a compact construction. However these tool cases are inconvenient and difficult to disassemble (for example when a case is broken and needs to be repaired). In addition, the assembly cannot be conveniently disassembled for carriage or transport.